Circles a and b are externally tangent to each other. from center b a tangent is drawn to circle a intersecting the circle at c. if bc is twice the radius of circle a compute the ratio of the area of circle a to the area of circle b.

Achange in any of the following factors will cause investment spending and aggregate demand to change excepta. the interest rate effect b. expected business conditionsc. real interest rate d. expected future returns created by new technology e. expected business taxes

The process that keeps heat from being transffered between two substances

Professor king finds out that the results of her study on visual and auditory stimuli and activity in the right hemisphere of the brain are statistically significant. what does it mean when the results of a study are statistically significant?